On the embedding of the Ω-saturation of a topological space

Abstract

The countably-compactification of a topological space X is such its extension Y, that Y is a completely regular and countably-compact space, and any closed countably-compact subset of X is closed in Y. But this extension does not always exist. Due to this, the concept of a saturation of a topological space appeared, which is a generalisation of the countably-compactification: instead of the condition of the countably-compactness of Y, it is necessary that any infinite subset of X has a limit point in Y. Meanwhile, the second condition remains unchanged. Such an extension is already defined for any T1-space. In this paper we consider a specific construction of saturation named as Ω-saturation. It is proved that under some additional (necessary and sufficient) condition to the separation of the initial space X, its Ω-saturation is canonically embedded in the Stone – Čech compactification βX. An analogous result is obtained for the countably-compactification by K. Morita.